54 Mr. Cameron on the 



look upon Aigilips as having any affinity with Allotria, from 

 which it differs in the rugose scutellum, in the shorter second 

 abdominal segment (which is not half the length of the 

 abdomen) and in the cubitus issuing from below the middle 

 of the transverse basal nervure. It is however very probable 

 that Aigilips Ashmead is different from Aigilips Hal. 

 Certainly that genus has a transverse groove before the 

 scutellum, the second abdominal segment is not " longer than 

 the others," and the parapsidal furrows are not parallel, as 

 stated by Mr. Ashmead to be the case with his Aigilips. 



According to our present knowledge the Allotrincs are 

 attached to aphides, either as parasites or hyper-parasites 

 of the ichneumons which destroy the plant lice. So far 

 I am acquainted with thirty-three British species oi Allotria. 

 Those with the wings fully developed may be known by 

 the following table : — 



1 (31) Radial cellule closed. 



2 (10) Thorax (and head) more or less red. 



3 (4) Thorax entirely red ; wings large, antennre and legs entirely clear 



yellow. Megaptera, Cam. 



4 (3) Thorax not entirely red, antennie not entirely yellow. 



5 (6) Pleurse entirely, and base of abdomen broadly rufous ; legs clear 



yellow, nervures yellow ; antenna; with the apical three-fourths 

 dark fuscous. Pktiralis, Cam. 



6 (5) Pleurce not entirely, and base of abdomen but slightly rufous ; 



nervures fuscous. 



7 (8) Lower part of pleurae piceous-red ; legs rufo-testaceous ; radial 



cellule small, one half longer than wide. Rtificeps, Cam. 



8 (7) Pleurae rufous, the centre broadly blackish, legs yellow ; radial 



cellule large, twice longer than wide. RiificolUs, Cam. 



9 (i) Thorax, head and basal half of abdomen castaneous ; legs tes- 



taceous ; radial cellule elongated, three times longer than wide. 



Collina, sp. now 



10 (21) Thorax black. 



11 (16) Head red. 



12 (13) Antennce uni-colorous yellow ; legs clear yellow. 



Flavicornis, ITtg. 



13 (12) Antennae fuscous, yellow at the base. 



14 (15) Head entirely red ; radial cellule elongate. FzV/r/jir, West, 



15 (14) Head with the vertex castaneous; radial cellule moderate. 



Tscheki, Gir. 



